Gradient instrument.



0.3. CRIM GRADIENT IN STBUMENT.

APPLICATION FILED HAY 9, 1908.

Patented Oct. 20, 1908.

wammu 7 CHARLES B. CRIM, OF SEATTLE, WA SHINGTON.

GRADIENT INSTRUMENT.

Specification of Letters Patent.

Patented Oct. 20, 1908.

Application filed May 9, 1908. Serial No, 431,788.

To all whom it may concern:

Be it known that I, CHARLES B. CRIM, a

citizen of the United States of'America, re-

siding at Seattle, in the county of King and State of Washington, have invented new and useful Improvements in Gradient Instruments, of which the following is a specification.

This invention relates to gradient instruments or instrumentsof precision for accurately determining angles, slopes and grades, the object of the invention being to provide a simpleand accurate instrument especially designed for topographical surveying, also to designate with accuracy grades, slopes and levels, the instrument taking the place of the common slope board or clinometer and being useful in lieu of the ordinary hand level for taking contour topography, the instrument providing for the instantaneous observation of the appropriate graduation on the scale immediately upon the registration of the cross strand or hair with the object and eye illustrating the relation between the reflector tical cross-section through the instrument iece of the instrument.

With the above and other objects, the invention consists in the novel construction,

combination and arrangement of parts as hereinafter fully described, illustrated and claimed. 1 v

In the accompanying drawing, Figure 1 is a side elevation of the instrument artly in section. Fig. 2 is a side elevation tl iereof and the graduated scale when the body of the instrument is inclined. Fig. 3 is a reverse elevation of the instrument showing the compass; and ig. 4 is an enlarged vershowing the graduations on the scale.

Referring to the drawings, 1 designates the .mainbody or case of the instrument which may be rectangular or of any preferred shape, the said case having mounted thereon a telescope 2 comprising a lens 8. at one end and an eye piece 4 at the other end. Arranged adjacent to the lens 3 is a cross strand or hair 5 disposed horizontally while arranged centrally of the telescope is a reflector 6 disposed at an angle of 45 with respect to the axis of the telescope.

Arranged in the case 1 below the telescope is a graduated scale bearing member 7 which is mounted on a pivot 8 to swin freely adapting the same to be accurate y positioned by gravity, the scale bearing mem-' her, for that purpose, being provided with a counterpoise 9 extending laterally in opposite directions, as shown in Fig. 1, and

.provided with adjustable balances 10, preferably in the form of threaded plugs, as shown, adapted to be screwed inwardly and outwardly in threaded sockets 11 in the counterpoise 9.

The arcuate edge or periphery of the memher 7 is graduated as shown at ,12 in Fig. 4:, the graduations running from O upward. The lower section of one side of the, case is hinged as shown at 13 to allow such portion of the case to be swung outward and upward to give access to the interior of the case for adjusting the balances 10. In the opposite side of the case there is arranged a compass l l.

In the use of the instrument, the operator looking through the eye piece 4, adjusts the angularity or inclination of the instrument until the cross hair or strand 5 registers with the desired object. He then glances at the reflector 6 which reflects the appropriate graduation on the member 7. The operator immediately ascertains by observation the degree or angle required. By reference to Fig. I it will be observed that the reflector 6 extends only part way across the telescope thereby enabling the strand or cross hair 5 tov be simultaneously observed. To adjust the instrument, the telescope is brought to a perm fectly horizontal position by any suitable 1. In an instrument of the class described,

the combination with a balanced scale bearing member, of a telescope embodying an eye piece, a cross strand, and a reflector, the lat ter being arranged to display the graduations of the scale and indicate the relation between such graduations and the cross strand.

2. In an instrument of the class described, a pivotally mounted scale bearing member,

means for balancing the same, and an observation device embodying an eye piece, a cross strand, and a reflector arranged to permit the vision to simultaneously take in the cross strand and the graduations of the scale.-

3. In an instrument of the class described, a balanced scale bearing member, in combination with an observation device comprising an eye piece at one end, a cross strand located at a distance from the eye piece, and a rellector set at an angle to the line of vision able balances having a threaded engage ent 10 and" of a width permitting a simultaneous with the scale bearing member, substantially view of the cross strand and the adjacent as described. graduations of the scale. In testimon whereof I affix my signature 5 4. In an instrument of the class described, in presence 0 two witnesses.

the combination with an observation device CHARLES B. CRIM. embodying an eye piece, a cross strand, and- Witnesses a reflector, of a case, a scale bearing member G. W. SLATER,

pivotally supported in said case, and adjust- FRED GRAHAM. 

